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crackbrain

American  
[krak-breyn] / ˈkrækˌbreɪn /

noun

  1. a foolish, senseless, or insane person.

crackbrain British  
/ ˈkrækˌbreɪn /

noun

  1. a person who is insane

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of crackbrain

First recorded in 1560–70; crack(ed) + brain

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Such a crackbrain as thou art, I never saw the like to it.

From A Select Collection of Old English Plays, Volume 2 by Hazlitt, William Carew

Hardly a hero, or crackbrain, or rantipole in Europe, one would think, but must have been then on exhibition somewhere in Naples.

From Modern Leaders: Being a Series of Biographical Sketches by McCarthy, Justin

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.